Generation of an atlas of the proximal femur and its application to trabecular bone analysis

Automatic placement of anatomically corresponding volumes of interest and comparison of parameters against a standard of reference are essential components in studies of trabecular bone. Only recently, in vivo MR images of the proximal femur, an important fracture site, could be acquired with high‐spatial resolution. The purpose of this MRI trabecular bone study was two‐fold: (1) to generate an atlas of the proximal femur to automatically place anatomically corresponding volumes of interest in a population study and (2) to demonstrate how mean models of geodesic topological analysis parameters can be generated to be used as potential standard of reference. Ten females were used to generate the atlas and geodesic topological analysis models, and 10 females were used to demonstrate the atlas‐based trabecular bone analysis. All alignments were based on three‐dimensional (3D) multiresolution affine transformations followed by 3D multiresolution free‐form deformations. Mean distances less than 1 mm between aligned femora, and sharp edges in the atlas and in fused gray‐level images of registered femora indicated that the anatomical variability was well accommodated and explained by the free‐form deformations. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.     

Average shape standard atlas for the adult Drosophila ventral nerve cord

Neuroanatomy benefits from quantification of neural structures, i.e., neurons, circuits, and brain parts, within a common reference system. Recent improvements in imaging techniques and increased computational power have made the creation of Web‐based databases possible, which serve as common platforms for incorporating anatomical data. This study establishes a standard average shape atlas for the ventral nerve cord (VNC) of Drosophila melanogaster. This atlas allows for the registration of morphological, developmental, and genetic data into one quantitative 3D reference system. The standard is based on an average adult Drosophila VNC neuropil as labeled in 24 whole‐mount preparations with the commercially available antibody (nc82) recognizing the Drosophila Bruchpilot protein (Brp). For the standardization procedure no expert knowledge of brain anatomy is required and global thresholding as well as straightforward affine and elastic registration procedures minimize user interactions. Successful registration is demonstrated for tracts and commissures, gene expression patterns, and geometric reconstructions of individual neurons. Any structure that is counterstained with anti‐Brp can be registered into the standard, allowing for fast comparison of data from different experiments and different laboratories. In addition, standard transformations can be applied to gray scale image data, so that any confocal image stack that is colabeled with anti‐Brp can be analyzed within standardized 3D reference coordinates. This allows for the creation of putative neural connectivity maps and the comparison of expression patterns derived from different preparations. The standard and protocols for histological methods, segmentation, and registration procedures will be made available on the Web. J. Comp. Neurol. 518:2437–2455, 2010. © 2010 Wiley‐Liss, Inc.     

Distribution and quantification of corticotropin-releasing hormone (CRH) in the brain of the teleost fish Oreochromis mossambicus (tilapia)

The recent characterization of the corticotropin-releasing hormone (CRH) prehormone of the fish tilapia (Oreochromis mossambicus) showed that more variation exists between vertebrate CRH amino acid sequences than recognized before. The present study investigates whether the deviating composition of tilapia CRH coincides with an atypical distribution of CRH in the brain. For this purpose we applied immunohistochemistry, as well as radioimmunoassay (RIA) quantification in brain slices. The results are plotted in a new atlas and reconstruction of the tilapia brain. The largest population of CRH-immunoreactive (ir) neurons is present in the lateral part of the ventral telencephalon (Vl). Approximately tenfold less CRH-ir neurons are observed in the preoptic and tuberal region. The CRH-ir neurons observed in the preoptic region are parvocellular and do not, or hardly, display arginine-vasotocin (AVT) immunoreactivity. CRH-ir neurons are also present in the glomerular layer of the olfactory bulb, in the periventricular layer of the optic tectum, and caudal to the glomerular nucleus. A very dense plexus of CRH-ir terminals is located in the most rostral part of the dorsal telencephalon. This region has not been described in other teleosts and is in the present study subdivided into the anterior part of the dorsal telencephalon (Da) and the anterior part of the laterodorsal telencephalon (Dla). High densities of CRH-ir terminals were observed in and around Vl, in the tuberal region, around the rostral part of the lateral recess, and in the caudal part of the vagal lobe. In the pituitary, CRH-ir terminals are concentrated in the neuro-intermediate lobe. Overall, the immunohistochemical and quantitative data correlated well, as the RIA CRH profile in serial 160-microm slices revealed four peaks, which corresponded with major ir-cell groups and terminal fields. Our results strongly suggest that the CRH-ir cells of Vl project to the rostro-dorsal telencephalon. Consequently, they may not be primarily involved in regulation of pituitary cell types but may subserve other functions. The presence of a CRH-containing Vl-Da/Dla projection seems to be restricted to the most modern group of teleosts, i.e., the Acanthopterygians. Further anatomic indications for non-pituitary-related functions of CRH are found in the vagal lobe and the optic tectum of tilapia. Although the low CRH content of the preoptic region reported here for tilapia may be typical for unstressed fish, the fact remains that remarkably few CRH-ir neurons are involved in regulating the pituitary. Overall, the CRH distribution in the brain of tilapia is more widespread than previously reported for other teleosts.     

中医脉象的客观检测和描述

以中医脉学经典著作《濒湖脉学》为蓝本,通过分析研究,论证了全部中医脉象客观检测和描述的可能性及方法,并提出了完整的中医脉象图谱结构     

三七DNA指纹图谱分析

目的:对文山三七和广西三七进行DNA指纹图谱的鉴别研究,了解其间遗传变异的大小,并建立三七品种的检定方法。方法:采用RAPD技术。结果:从45个引物中筛选出23个扩增稳定且谱带清晰的引物,共得到211个遗传标记。DNA指纹图谱显示,样品间有遗传差异,具有不同的遗传特征,据此可进行鉴别。结论:RAPD技术可作为三七鉴别的参考方法。     

野生天麻和栽培天麻的DNA指纹图谱分析

目的:对野生天麻和三种人工栽培天麻进行DNA指纹图谱的鉴别研究,了解其间遗传变异的大小,并建立天麻品种的检定方法。方法:采用RAPD技术。结果:从45个引物中筛选出23个扩增稳定且谱带清晰的引物,共得到209个遗传标记。DNA指纹图谱显示,各样品间有遗传差异,具有不同的遗传特征,据此可进行鉴别。结论:RAPD技术可作为天麻鉴别的参考方法。     

An atlas of the deep cerebellar nuclei and subtentorial brainstem of the cat with compensation for skull-size

BERNTSON, G. G., T. S. PAULUCCI AND M. W. TORELLO. An atlas of the deep cerebellar nuclei and subtentorialbrainstem of the cat, with compensation for skull-size. BRAIN RES. BULL. 3(5)475–492, 1978.—The bony tentorium in the cat precludes a stereotaxic approach, in the coronal plane, to widespread areas of the cerebellum and underlying brainstem. To facilitate the application of the stereotaxic method in these areas, an atlas of the subtentorial brainstem was prepared, with plates (30° from the vertical) based on an angle of entry which avoids the tentorium. In addition, a placement error regression function, based on a measure of skull size, was derived to provide atlas coordinate corrections for different brain sizes. The application of this regression function, together with the present atlas plates, can greatly increase placement accuracy.     

Functional-anatomical validation and individual variation of diffusion tractography-based segmentation of the human thalamus

Parcellation of the human thalamus based on cortical connectivity information inferred from non-invasive diffusion-weighted images identifies sub-regions that we have proposed correspond to nuclei. Here we test the functional and anatomical validity of this proposal by comparing data from diffusion tractography, cytoarchitecture and functional imaging. We acquired diffusion imaging data in eleven healthy subjects and performed probabilistic tractography from voxels within the thalamus. Cortical connectivity information was used to divide the thalamus into sub-regions with highest probability of connectivity to distinct cortical areas. The relative volumes of these connectivity-defined sub-regions correlate well with volumetric predictions based on a histological atlas. Previously reported centres of functional activation within the thalamus during motor or executive tasks co-localize within atlas regions showing high probabilities of connection to motor or prefrontal cortices, respectively. This work provides a powerful validation of quantitative grey matter segmentation using diffusion tractography in humans. Co-registering thalamic sub-regions from 11 healthy individuals characterizes inter-individual variation in segmentation and results in a population-based atlas of the human thalamus that can be used to assign likely anatomical labels to thalamic locations in standard brain space. This provides a tool for specific localization of functional activations or lesions to putative thalamic nuclei.     

The cerefy brain atlases

The Talairach-Tournoux (TT) atlas is probably the most often used brain atlas. We overview briefly the activities in developments of electronic versions of the TT atlas and focus on our more than 10-yr efforts in its continuous enhancement resulting in three main versions: TT-1997, TT-2000, and TT-2004. The recent TT-2004 version is substantially improved over the digitized print original with a higher structure parcellation, better quality and resolution of individual structures, and improved three-dimensional (3D) spatial consistency. It is also much more suitable for developing atlas-based applications owing to pure color-coding (for automatic structure labeling), contour representation (to avoid scan blocking by the overlaid atlas), and color cross-atlas consistency (for the simultaneous use of multiple atlases). We also provide a procedure for 3D spatial consistency improvement and illustrate its use. Finally, we present some of our latest atlas-assisted applications for fast and automatic interpretation of morphological, stroke, and molecular images, and discuss the future steps in TT atlas enhancement.